US5877419A
Expired / Lapsed
US
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Method for estimating the service life of a power semiconductor component
Assignee: Siemens AG
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Filing: 1997-03-04
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Granted: 1999-03-02
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Expires: 2017-03-04
Abstract
Abstract A method which exploits the phenomenon that an increase of the collector-emitter voltage UCE of a semiconductor power component during a load change test can be correlated with the service life expectancy of the relevant IGBT module. A method for estimating the service life of a power semiconductor component, comprising the steps of subjecting the component to a periodic load change, measuring an electrical parameter P of the component that serves as an indicator for reliability or durability against the number N of load changes, calculating a derivative dP/dN of the electrical parameter P according to the number N of load changes; and comparing the derivative dP/dN with a target value representing a determined service life. The characteristic "longer-lived than a reference module" or, respectively, "more resistant to failure" can be allocated to a test module if the derivatives of the respective voltage UCE satisfy the condition (dUCE/dN)Test<(dUCE/dN)Ref after the number N of load changes.
Inventors
- 👤 Babak Farokhzad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:56
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; G01R31/2607; G01R31/2608; H; H10; H10W; H10W72/00; H10W72/50; H10W72/531; H10W72/5363; H10W72/541; H10W72/547; H10W72/5473
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
77 words
A method for estimating the service life of an IGBT, comprising the steps of: subjecting the IGBT to a periodic load change; measuring an electrical parameter P of the IGBT that serves as an indicator for reliability or durability against the number N of load changes; calculating a derivative dP/dN of the electrical parameter P according to the number N of load changes; and comparing the derivative dP/dN with a target value representing a determined service life.
Claim 2
Independent Claim
77 words
A method for estimating the service life of an IGBT, comprising the steps of: subjecting the IGBT to a periodic load change; measuring an electrical parameter P of the IGBT that serves as an indicator for reliability or durability against the number N of load changes; calculating a derivative dP/dN of the electrical parameter P according to the number N of load changes; and comparing the derivative dP/dN with a target value representing a determined service life.
Claim 3
Dependent Claim
36 words
The method according to claim 1, wherein the derivative dP/dN is compared with a derivative (dP/dN) Ref , measured for a reference element under the same conditions and within the same interval of N load changes.
Claim 4
Dependent Claim
63 words
The method according to claim 2, wherein the IGBT is rated as longer-lived in relation to the reference element as long as the condition dP/dN<(dP/dN).sub.Ref is satisfied within the interval of N load changes and in that the IGBT is rated shorter-lived in relation to the reference element as long as the condition dP/dN>(dP/dN).sub.Ref is satisfied within the interval of N load changes.
Claim 5
Dependent Claim
35 words
The method according to claim 2, wherein at least a second derivative d 2 P/dN 2 is calculated and compared with a corresponding second derivative (d 2 P/dN 2 ) Ref of the reference element.
Claim 6
Dependent Claim
22 words
The method according to claim 2, wherein a warning signal is produced if the derivative dP/dN is larger than the target value.
Claim 7
Independent Claim
45 words
The method according to any one of claims 1 to 5, wherein the parameter P is selected from the group consisting of a potential difference between two terminals of the IGBT, an ohmic resistance between two terminals or an ohmic resistance of an IGBT terminal.
Claim 8
Dependent Claim
69 words
The method according to claim 6, wherein the IGBT comprises an emitter terminal, an auxiliary emitter terminal and a collector terminal, a resistance (R EH ) between the emitter terminal and the auxiliary emitter terminal, a resistance of the emitter (R E ) or a resistance of the auxiliary emitter (R H ), or a collector-emitter voltage (U CEsat ) is measured against the number N of load changes.
Claim 9
Independent Claim
213 words
A method for estimating the service life of an IGBT, comprising the steps of: subjecting the IGBT to a periodic load change; measuring an electrical parameter P of the IGBT that serves as an indicator for reliability or durability against the number N of load changes; calculating a derivative dP/dN of the electrical parameter P according to the number N of load changes; and comparing the derivative dP/dN with a target value representing a determined service life, wherein the derivative dP/dN is compared with a derivative (dP/dN) Ref , measured for a reference element under the same conditions and within the same interval of N load changes, wherein at least a second derivative is calculated, wherein the parameter P is selected from the group consisting of a potential difference between two terminals of the IGBT, an ohmic resistance between two terminals or an ohmic resistance of an IGBT terminal, and wherein the IGBT comprises an emitter terminal, an auxiliary emitter terminal and a collector terminal, a resistance (R EH ) between the emitter terminal and the auxiliary emitter terminal, a resistance of the emitter (R E ) or a resistance of the auxiliary emitter (R H ), or a collector-emitter voltage (U CEsat ) is measured against the number N of load changes.
Claim 10
Independent Claim
213 words
A method for estimating the service life of an IGBT, comprising the steps of: subjecting the IGBT to a periodic load change; measuring an electrical parameter P of the IGBT that serves as an indicator for reliability or durability against the number N of load changes; calculating a derivative dP/dN of the electrical parameter P according to the number N of load changes; and comparing the derivative dP/dN with a target value representing a determined service life, wherein the derivative dP/dN is compared with a derivative (dP/dN) Ref , measured for a reference element under the same conditions and within the same interval of N load changes, wherein at least a second derivative is calculated, wherein the parameter P is selected from the group consisting of a potential difference between two terminals of the IGBT, an ohmic resistance between two terminals or an ohmic resistance of an IGBT terminal, and wherein the IGBT comprises an emitter terminal, an auxiliary emitter terminal and a collector terminal, a resistance (R EH ) between the emitter terminal and the auxiliary emitter terminal, a resistance of the emitter (R E ) or a resistance of the auxiliary emitter (R H ), or a collector-emitter voltage (U CEsat ) is measured against the number N of load changes.
Claim 11
Dependent Claim
63 words
The method according to claim 8, wherein the IGBT is rated as longer-lived in relation to the reference element as long as the condition dP/dN<(dP/dN).sub.Ref is satisfied within the interval of N load changes and in that the IGBT is rated shorter-lived in relation to the reference element as long as the condition dP/dN>(dP/dN).sub.Ref is satisfied within the interval of N load changes.
Claim 12
Dependent Claim
24 words
The method according to claim 8 or 9, wherein a warning signal is produced if the derivative dP/dN is larger than the target value.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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